Trailer steering mechanism



Nov. 9, 1943. AVERY v 2,333,912

TRAILER STEERING MECHANISM Filed April 29. 1942 2 Sheets-Sheet .1

INVENTOR. fl0//01s .3 Every Nov. 9, 1943. D. B. AVERY TRAILER STEERING MECHANISM Filed April 29. 1942 2 Sheets-Sheet 2 Patented Nov. 9, 1943 UNITED STATES PATENT OFFICE.

TRAILER STEERING MECHANISM I Dallas 3. Avery, Oapac, Mich. Application April 29, 1942, Serial No. 441,040

Claims.

This invention relates to automobile trailer 2 construction and particularly involves new and improved mechanism actuated by the turning of a tractor for steering the forward and rear wheels of the trailer so that the rear wheels of the.

trailer when the trailer is turned are caused to follow the tracks of the forward trailer wheels.

. A further object of the invention is to provide means forming part of the trailer construction to which a tractor vehicle. is connected and by the turning of the tractor vehicle the mechanism for turning the wheels of the trailer is actuated to cause the trailer wheels to follow the track of the rear wheels of the tractor to thus avoid the necessity of the trailer wheels making a newtrack in softearth or snow and thus reducing the load on the tractor.

These and various other objectsvand features of my invention are hereinafter more fully described and claimed and the preferred form of construction of an automobile trailer running gear is shown in the'accompanyingdrawings in Fig. 1 is a plan view showing my improved trailer steeringmechanism and manner of connection thereof with a, tractor. I

Fig. 2 is an enlarged vertical section taken .on

line 22 of Fig. -1- showing the forward wheels of the trailer carried by a sub-frame to which the tractor is connected.- Fig. 3 is a horizontal section taken on line 3-3 of Fig. 2. Y I i In the usual four wheeled trailer structures the front and rear axlesare fixed to the trailer frame and thus the wheels of the trailer do not tend to follow the wheel tracks of the tractor in passing around a -,.curve. 'My improvedv trailer mechanism involves means for turning the wheels of the trailer as a resultof change in direction of movement of the tractor to cause the trailer wheels to follow the track -made by the tractor wheels,and further to cause the rear wheels of the tractor to turn at an opposite angle to the angle of .the forward wheels in respect to; the longitudinal center line of the trailerto cause the rear trailer wheels to follow the track of'the forward trailer wheels.

In Fig. 1 the rear end of the tractor is indi-i cated at l to which the V shaped tongue 2 is vertically: pivoted at its apex to the pivotpin 3 securing'the same to the tractor and has-two horizontally spaced opposite ends pivoted to .the

brackets 4 by the bolts 5 to turn on a horizontal axis. The brackets 4 are attached to the forward end of a sub-frame 8 as will be more clearly understood from Fig. 2. The sub-frame is preferably of. rectangular form and the front axle I of the trailer is spring supportedto the sub-.

frame 6 as by leaf springs 8 there being a leaf .spring 8 onopposite sides of the .pivotal axis of the sub-frame 6. The wheels 9 are rotatably supported atopposite ends of the axis 1 andby the turning of the sub-frame 6 as shown by dotted lines in Figl the wheels are turned in angular relation tothe parallel side members In and l I'of the trailer'frame. 4 I I The sub-frame 6 carrying the front axle in fixed transverse relation therewith has the cross f cally spaced its center from the plate I5. The plates l5 and "thrive aligned apertures to receive a vertical shaft l1 s'uppo'rted'by a bearing element lil'in the plate I5 and a bearing element I'Ba in the plate 16. Intermediate the sai'd'bea'r' ing elements theverticals haft' IT has a'horiz o'ntal flange 19 to which is secured 'a beveled gear" 20 on the lower face of which the teeth are pro Vided and which mesh 'with'a'pinion fl carried on the shaft 22. The pinion 2| is rotatably sup'f ported in-a projecting arm lBa' fixed to the plate 16. The plate It has opposite flanged ends IBD and Hie which as shown'in Fig; 2 are bolted to the-"plate l5. Thus the plate l6, arm 16a and the shaft 22 are held in fixed position while the sub-frame 6 may turnon the axis of theshaft l1. The upper face of the crossplate 12 has an opening to receivea' block 23 which is pinned to the lower end. of the vehicle'shaft l1 and has a square side member 24: extending into a recess'in the-upper face of the cross member l2. By turning the sub-frame 6, axle- 1 carrying the forward wheels 9-the shaft i! will be turnedona vertical axis. therebyrotating the gear 20 pinion 2| and shaft 22. The shaft 22 is connected by a universal joint 25 with a shaft 26'supported in-the side" frame ill of the trailer as will be. understood-from Fig. 1. The shaft'26 has aworm V21 thereon which meshes with a segmental worm gear-2 8- which is supportedby a casting 29 secured to the vehicle frame by bolts 30. The segmental gear 28 hasan arm 3| fixed thereto at one end andto the opposite endof which. is pivoted an end of the arm 32/ The opposite end of the arm 32 isv vertical axis and this arm is connected by the rod 40 to a pivot member 4| to which the arm 32 is connected. The opposite end of the rod 40 is pivoted at 42 to the bracket 38. Thus by turning of the arm 3| by the gear segment 28 both the rear wheels of the tractor are turned to like extent to occupy an angular position relative to the fixed shaft 34 and side of the trailer frame and at an opposite angle to that occupied by the wheels 9.

By this arrangement the rear wheels are caused to carry the rear end of the trailer in a direction opposite thedirection of movement of the front end of: the trailerj The rear wheels thus follow the arcuate path of the front wheels when the tractor .vehicle is turned in one direction or the other from the longitudinal center line of the trailer-frame whichpasses through theaxis of the pint. I

It should be borne in mind that theturning' of the tractor to produce a side pull on the trailer;

tongue2 horizontally pivoted to the sub-frame 6 causes the sub-frame to turnon a vertical axis as indicated by the dotted lin'es in Fig. land it is the turnin of this sub-frame on the axis of the vertical shaft 11 that rotates the shafts 22 and r to turn the rear. wheelson their pivots at the opposite ends of the axle and the turning of these rear wheels 36 and 31 on their pivots causes the trailer frame H to turn on the axis of the shaft,- lfl. The rear end of the trailer is therefore caused to traverse substantially the same arcuate path as the front wheels 9 on opposite ends of the axle "I.

The front w heels 9 of the trailer are caused to follow the track of the rear wheels of the trailer as the sidepull of the trailer on the. pivoted tongue 2, attached to the sub-frame twill turn the movement of the tractor. This tends tocarry the rear end of the trailer frame outwardly in respect to the arc of movement of the forward wheels of the trailer and thus cause the rear trailerwheels' to follow the track of the front trailer wheels.

It is further to be observed that'the front trailer wheels are caused to'followthe track of the rear wheels of .the tractor due to the fact that the tongue 2 of the trailer'sub-fram'eis pivoted to turn on a vertical axis relative "to the trailer.

The turning of the trailer in one direction or theotherexerts aside thrust on the trailer tongue 2' and'consequently the trailersub-frarne 6 and wheels 9 on the axis of the'shaft l1. Thus the: front axle carrying the wheels! onfbeing turned about the axis 'of" the shaft I I, as the tractor'turns one side or the other, causes the front wheels 9 of the trailer to, follow thetracks tional relationship thereof, that an automobile trailer according to my invention is comparatively simple and inexpensive and that various changes and modifications may be made in the form and arrangement of the parts without departing from the spirit and scope of the invention as set forth in the claims. 2

Having thus fully described my invention, its

utility and mode'of operation, what I claim and I desire to secure by Letters *Batent of;,tha*United States is: I 1

1. A four wheeled automobile trailer comprising a main frame, a rear axle supported at the rear end of and in fixed relation with the main frame, wheel elements pivoted to turn on a verticalaxis at opposite ends of the rear axle, a front axle, wheel elements rotatably mounted on II eluding a gear-actuated by rotation ofthe said supporting .the front axle, I pivotally su'pof the rear tractor wheelsnot shown in'the draw-' It is believed evident from the foregoing del scription of the parts and structuralrand func-' the opposite ends of the front axle, a sub-frame supporting the front axle, means pivotally supporting the sub-frame on the forward portion of the main frame to permit turning of the subframe on a vertical axis, a tongue attached to the sub-frame at one end, and adapted to be' pivotally connected with the tractor element to' permit turning of the tractor element whereby change in direction of movement of the tractor" causes the sub-frame to'turn on a vertical'axis;

a gear turnablewith the-sub-framd'means infir'st named gear to turn wheels on pivots at a reverse angle and to the same degree as the wheels of the front axle are turnedby the tractor. v I I I 2. A four wheeled automobile trailer compris tical axis at opposite of'the rear axlefa the opposite ends of the front axle, a sub-frame porting the sub frame on the forward portion of the main frame to permit turningof theambframeon a vertical axis, a tongue attached to the sub-frame at one end, and adapted to 1 be piv-' otally connected with the tractor element to per-- mitturn'lng of the tractor element whereby change in direction of'movement of the tractor a gear turnable with the'sub-frame; 'and' f ,1 3 including a worm gear'rotatable' by th first named gear, a gear segment meshing with-the saidworrn, and means connected-with the gear segment whereby turning thereof by the worm reverse of that to which the wheels of axle are turned by the tractor.

' thefmnt axle is securedrmeans pivotally porting the sub-frame to turn on a vertical'axis relative to the forward portion of the mainframe,

a. tongue pivotally attached to the, sub-frame to turn on a horizontal axis andfadapted to be I pivotally connected to a tractor elementtoper mit the tractor element to turn on a verticaliaxis in respect to the Itonguewhereby a side draft on the tongue by the tractor turns the front frame, a gear carried at the forward end of the trailer I frame and secured to turn on the pivot of the sub-frame, a gear means'supported at the rear inga main frame, a rear axlesupported at the rear end of and in fixed relation with the main; frame, wheel elements pivotedto turn'o'n a-vei 5 Icauses' the sub-frame to turn'on a vertical axis,

gear turns the rear wheelson'their respective pivots to the same degree and at an angle the the front" of the trailer frame, means operatively connecting the said last named gear with the gear at the forward end of the main frame, and means between the gear carried at the rear of the frame and the rear wheels whereby rotation of the last named gear turns the rear wheels on their pivot at an opposed angle to that to which the front wheels are turned by the tractor element.

4. A four wheeled trailer vehicle comprising a main frame, a rear axle supported at the rear end of the main frame, a wheel element pivotally attached to each of the opposite ends of the rear axle to turn on a vertical axis, a front axle, wheel elements rotatably secured to opposite ends of the front axle, a sub-frame supporting the front axle, means including a vertical shaft pivotally supporting the sub-frame to the forward end of the main frame and fixed to the sub-frame, a

gear on the said shaft and rotatable therewith, a shaft connected to the last named gear, a worm on the said shaft supported by the main frame, a worm gear actuated by rotation of the worm, steering knuckles on each of the rear wheels for turning the same on a vertical axis, and a con nection between the worm gear and the said steering knuckles, said shafting and gear train providing a means whereby the turning of the sub-frame and front wheels on a vertical axis to an angular position in respect to the longitudinal center line of the main frame causes the rear wheels to turn on their vertical axes at an angle opposite and equal to the angle to which the front wheels may be turned by the sub-frame.

5. A four wheeled trailer vehicle comprising a main frame, a, rear axle spring supported in respect to the main frame, a wheel element pivotally supported at each of the opposite ends of the rear axle to turn on a vertical axis, a front axle, wheel elements rotatably secured on opposite ends of the front axle, a sub-frame, spring means supporting the front axle relative to the sub-frame, means including a vertical shaft pivotally'supporting the sub-frame to the forward end of the main frame and fixed to turn with the said frame, means being the vertical shaft and the rear wheels whereby turning of the subframe and vertical shaft causes the rear wheels to turn on their vertical, axes at an angle to the longitudinal axis of the main frame corresponding to and the reverse of the angle to which the front wheels are turned by the turning of the sub-frame.

DALLAS B. AVERY.

CERTIFICATE OF CORRECTION.

Patent No. 2,5553912. November 9, 19145.

DALLAS B AVERY It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 5, sec

0nd column, line 18, claim 5, for "means being" read means between-;

and that the said Letters Patent should be readwith this correction there in that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 8th day of February, A. D. 19M.

Henry Van Arsdale, (S Acting Commissioner of Patents. 

